Exterior lamp assemblies for automotive vehicles generally include a light source and reflector for redirecting at least a portion of the light from the light source in a desired direction. In most reflector-type lamp assemblies, it is desirable to position the light source at or close to a focal point of the reflector so that rearward radiated light from the light source is reflected in a direction parallel to the optical axis of the reflector. Commonly, these lamp assemblies include a housing or other support member having a lamp socket in which the light source is mounted, with the housing and its socket and light source being installed such that the light source extends through a passage or thruway in the back of the reflector to position the light source at the focal point of the reflector. However, due to manufacturing tolerances and/or when the reflector and housing are mounted at least somewhat independently in a substantially fixed position relative to each other, it can be difficult to accurately locate the light source within the reflector since the socket help by the housing may not be accurately aligned with the thruway in the reflector.